Archives for August 2006
How Our Brain Works
The brain is a mass of nerve tissue that fills the entire inside of the skull. It is by far the most important organ in the body. Without it, we could not live.
The billions of tiny cells in the brain are remarkable. They remember things for years; they seem to be able to learn endless [...]
The Skeleton
The Skeleton
There are more than two hundred bones in the skeleton of each one of us. The skeleton supports all the structures of our body and gives us our shape. Bones are made up mostly of hard calcium, but inside them is a soft substance called bone marrow. In this marrow, blood cells of all [...]
The Circulatory System
The Heart
The heart is a hollow organ, with four chambers, made up of muscles that continuously contract and relax. It is located beneath the breastbone in the chest, mostly on the left side, although a small portion extends over to the right side of the chest. The heart pumps the blood through the body. Without [...]
The Large Intestines
The large intestines connect with the small intestines in the lower right part of the abdomen. They then extend up the right side of the abdomen to an area beneath the liver, cross the abdomen to the left side high up near the diaphragm, and, finally, extend down the left side of the abdomen all [...]
The Small Intestines
The small intestines are long muscular tubes that join the stomach to the large intestines. If they were outside the body and were straightened out, they would stretch out to about twenty feet, or about the length of most people’s living room! The first part of the small intestines is called the duodenum, the second [...]
The Stomach
The Pancreas
The pancreas is a gland that lies crosswise in the middle of the abdomen below the stomach. It makes insulin, a hormone that controls the way we use the sugar we have digested, and it manufactures various juices that flow into the intestines to help digest the foods we have eaten.
The Stomach
The stomach lies [...]
Liver and Small Intestine
The Liver
The liver is the largest organ in the body. It extends across the upper abdomen beneath the diaphragm, the muscle that separates the chest cavity from the abdominal cavity. The liver has more jobs to do than any other organ. It stores and releases into the blood the proteins, sugars, and fats that we [...]
Read ‘Liver and Small Intestine’
The Lungs
The lungs are located in the chest and are surrounded and protected by the ribs. They are two large spongy organs that get bigger as we breathe in and smaller as we breathe out. The lungs take out the oxygen from the air we breathe in and get rid of carbon dioxide with the air [...]